Fatty Acid Profile and Chemical Composition of Oil from Six Varieties of Lupine (Lupinus mutabilis) Consumed in Peru

Abstract

Background. The characterization and evaluation of the nutritional composition of lupine (Lupinus mutabilis) seeds has a long history. However, the determination of the fatty acid profile has only been carried out in a few varieties. Objective. This study determined the fatty acid profile and chemical composition of the oil of six varieties of lupine consumed in Peru. Methods. The extraction of oil from each lupine variety was carried out using the Soxhlet method. Fatty acids, moisture, acidity index, free fatty acids, peroxide value, iodine value, saponification value, and density were determined using official AOAC methods. Results. In general, the average values of saturated fatty acids are lower than those of unsaturated fatty acids. Among the monounsaturated fatty acids (MUFA), oleic acid (C18:1) was the most representative, with values ranging from 41.83% to 54.33%. The “Andenes” variety showed an average oleic acid value of 54.60% compared to the other varieties. The composition of polyunsaturated fatty acids (PUFA) was dominated by linoleic acid (C18:2), and the variety “Cholo fuerte” reported higher values (34.70%) compared to the other varieties. Likewise, the highest average PUFA was 36% and was observed in the “Cholo fuerte” variety. The concentration of linolenic fatty acid (C18:3) ranges from 2.1% for the “Andenes” variety to 2.9% for the common lupine. Additionally, the mean content of linolenic (ω-6) and linoleic (ω-3) acids was 2.33 and 30.89% (13 : 1 ratio), respectively, with the consequent ratio of ω-6/ω-3 fatty acids at the mean level of 0.08. All physicochemical characteristics of lupine seed oil are in accordance with the requirements for edible oils. Conclusion. These findings make the six lupine varieties a new source of promising food components of high nutritional value.